TL;DR: 2029 is Kỷ Dậu, with nạp âm Đại Trạch Thổ; the lunar year runs from Tết on 13 February 2029 to the end of 1 February 2030, while the Bát Tự year pillar begins at Lập Xuân, 20:19 on 3 February 2029. In the folk way of matching ages, the branch axis counts parents born in Tỵ, Sửu and Thìn years as favourable and Tý, Ngọ, Mão and Tuất years as unfavourable for a Dậu child; the stem axis is favourable with the stem Giáp; the nạp âm axis is favourable with Thổ, Hỏa and Kim parents and unfavourable with Mộc and Thủy. The axes often point different ways, and all are conventions, not scientific conclusions.
What stem, branch and nạp âm does the year 2029 Kỷ Dậu have?
2029 is the Kỷ Dậu year, the year of Dậu (the rooster). The stem Kỷ is yin Thổ (Earth), the branch Dậu is yin Kim (Metal); Thổ generates Kim, so the stem generates the branch. Mậu Thân and Kỷ Dậu share the nạp âm Đại Trạch Thổ (大驿土, Earth of the Great Marsh; some books read it Đại Dịch Thổ), of the Thổ element.
The book Hiệp kỷ biện phương thư, volume 1, quotes Đào Tông Nghi (Tao Zongyi) explaining the name of this nạp âm: "戊申己酉大驛土者，申為坤，坤為地，酉為兌，兌為澤". That is, Thân corresponds to the Khôn trigram, which is the earth, and Dậu to the Đoài trigram, which is the marsh; the Thổ of Mậu and Kỷ is laid on that earth and marsh, so "非其他浮薄之土也", it is not thin, floating soil.
The stem, branch and nạp âm of a year are calendrical data that can be calculated; inferring compatibility from them is a convention of the folk way of matching ages, not a datum.
When do the lunar year Kỷ Dậu and the Kỷ Dậu year pillar begin?
The lunar year Kỷ Dậu begins at Tết Nguyên đán on 13 February 2029 and runs to the end of 1 February 2030, since the Canh Tuất Tết falls on 2 February 2030; Tử Vi and the folk way of counting age use this boundary. The twelfth lunar month (tháng Chạp) of Kỷ Dậu runs from 4 January 2030 to the end of 1 February 2030, so for an expected birth date at the end of 2029 or the start of 2030 the lunar calendar should be checked for the exact day. Bát Tự takes the year pillar by the Lập Xuân solar term, which begins at 20:19 on 3 February 2029 and at 02:08 on 4 February 2030 (Vietnam time). So a baby born from 20:19 on 3 February 2029 to the end of 12 February 2029 is still a Mậu Thân by the lunar year but carries the Kỷ Dậu year pillar in Bát Tự; a baby born from 2 February 2030 until before 02:08 on 4 February 2030 is already a Canh Tuất by the lunar year but still carries the Kỷ Dậu year pillar.
The book Phong thủy thực hành trong xây dựng và kiến trúc nhà ở by Vũ Đức Huynh uses this very year as its example of a lunar year running into the next solar year: someone born in early January 2030 still has the lunar year Kỷ Dậu[1].
A child born in 2029 Kỷ Dậu is compatible with which parents' birth years?
The folk way of matching ages compares three things of the child's birth year with the birth year of each parent: the heavenly stem (combining or clashing), the earthly branch, that is the zodiac animal (tam hợp, lục hợp, tứ hành xung, lục hại), and the nạp âm element (generating or overcoming). Each axis rests on its own conventional table and gives its own conclusion, and the axes often point different ways:
- Earthly branch: Tỵ and Sửu form the tam hợp with Dậu, and Thìn is in lục hợp with Dậu; these three count as favourable. Tý, Ngọ and Mão are in the same tứ hành xung group as Dậu, Mão being Dậu's opposite branch; Tuất is in lục hại with Dậu; these four count as unfavourable. Parents born in a Dậu year share the child's branch, which is put in neither the combining nor the clashing groups; Dần, Mùi, Thân and Hợi have no relation with Dậu in these four tables.
- Heavenly stem: Kỷ combines with Giáp, so a parent whose birth-year stem is Giáp counts as favourable; Kỷ clashes with no stem in the stem-clash table.
- Nạp âm: Đại Trạch Thổ shares the element with Thổ parents, is generated by Hỏa parents and generates Kim parents; these three cases count as favourable. The child overcomes Thủy parents and is overcome by Mộc parents; these two cases count as unfavourable.
The table below applies these tables to parents born from 1984 to 2001 (lunar years: someone born in January or February before Tết belongs to the previous year):
| Parents' birth year | Nạp âm | Stem compared with Kỷ | Branch compared with Dậu | Nạp âm compared with Đại Trạch Thổ |
|---|---|---|---|---|
| 1984 Giáp Tý | Hải Trung Kim | Ngũ hợp, favourable | Tứ hành xung, unfavourable | Child generates parent, favourable |
| 1985 Ất Sửu | Hải Trung Kim | Neither combining nor clashing | Tam hợp, favourable | Child generates parent, favourable |
| 1986 Bính Dần | Lư Trung Hỏa | Neither combining nor clashing | Neither combining nor clashing | Parent generates child, favourable |
| 1987 Đinh Mão | Lư Trung Hỏa | Neither combining nor clashing | Tứ hành xung, unfavourable | Parent generates child, favourable |
| 1988 Mậu Thìn | Đại Lâm Mộc | Neither combining nor clashing | Lục hợp, favourable | Parent overcomes child, unfavourable |
| 1989 Kỷ Tỵ | Đại Lâm Mộc | Same stem | Tam hợp, favourable | Parent overcomes child, unfavourable |
| 1990 Canh Ngọ | Lộ Bàng Thổ | Neither combining nor clashing | Tứ hành xung, unfavourable | Same element, favourable |
| 1991 Tân Mùi | Lộ Bàng Thổ | Neither combining nor clashing | Neither combining nor clashing | Same element, favourable |
| 1992 Nhâm Thân | Kiếm Phong Kim | Neither combining nor clashing | Neither combining nor clashing | Child generates parent, favourable |
| 1993 Quý Dậu | Kiếm Phong Kim | Neither combining nor clashing | Same branch | Child generates parent, favourable |
| 1994 Giáp Tuất | Sơn Đầu Hỏa | Ngũ hợp, favourable | Lục hại, unfavourable | Parent generates child, favourable |
| 1995 Ất Hợi | Sơn Đầu Hỏa | Neither combining nor clashing | Neither combining nor clashing | Parent generates child, favourable |
| 1996 Bính Tý | Giản Hạ Thủy | Neither combining nor clashing | Tứ hành xung, unfavourable | Child overcomes parent, unfavourable |
| 1997 Đinh Sửu | Giản Hạ Thủy | Neither combining nor clashing | Tam hợp, favourable | Child overcomes parent, unfavourable |
| 1998 Mậu Dần | Thành Đầu Thổ | Neither combining nor clashing | Neither combining nor clashing | Same element, favourable |
| 1999 Kỷ Mão | Thành Đầu Thổ | Same stem | Tứ hành xung, unfavourable | Same element, favourable |
| 2000 Canh Thìn | Bạch Lạp Kim | Neither combining nor clashing | Lục hợp, favourable | Child generates parent, favourable |
| 2001 Tân Tỵ | Bạch Lạp Kim | Neither combining nor clashing | Tam hợp, favourable | Child generates parent, favourable |
On the stem axis two years in this range are favourable, 1984 Giáp Tý and 1994 Giáp Tuất; 1989 Kỷ Tỵ and 1999 Kỷ Mão share the stem Kỷ with the child, which counts as neither combining nor clashing. The same birth year can be favourable on one axis and unfavourable on another, as with 1984 Giáp Tý: the stem Giáp combines with Kỷ and Hải Trung Kim is generated by Đại Trạch Thổ, but Tý is in the same tứ hành xung group as Dậu. To check the exact birth years of the father and the mother, including the child's expected month and hour of birth, the Child's birth year by parents' ages tool can be used.
Which elements does the nạp âm Đại Trạch Thổ count as favourable?
By the five-phase generating and overcoming that the folk way of matching ages applies to nạp âm, Đại Trạch Thổ (Thổ element) counts as favourable with Thổ parents (same element), Hỏa parents (Hỏa generates Thổ) and Kim parents (Thổ generates Kim), and unfavourable with Mộc parents (Mộc overcomes Thổ) and Thủy parents (Thổ overcomes Thủy). On this axis it is the parent's Mộc that overcomes the child, not Đại Trạch Thổ that overcomes Mộc.
A more common mistake is to take the element of the branch instead of the nạp âm. Canh Thân (1980) and Tân Dậu (1981) have Kim branches but their nạp âm is Thạch Lựu Mộc; Kỷ Tỵ (1989) has a Hỏa branch but its nạp âm is Đại Lâm Mộc; Giáp Dần (1974) and Ất Mão (1975) have Mộc branches but their nạp âm is Đại Khê Thủy. A site that goes by the branch element and a site that goes by nạp âm can therefore reach two different conclusions for the same birth year.
Which parents' birth years count as unfavourable for a Dậu child?
On the branch axis, parents born in Tý, Ngọ and Mão years (the Tý Ngọ Mão Dậu tứ hành xung group) and in Tuất years (lục hại) count as unfavourable for a Dậu child. The other two axes can say the opposite: 1984 Giáp Tý and 1994 Giáp Tuất have the stem Giáp, which combines with the child's stem Kỷ; 1987 Đinh Mão, 1990 Canh Ngọ and 1999 Kỷ Mão count as favourable on the nạp âm axis. In the table above only 1996 Bính Tý is unfavourable on both the branch and the nạp âm axes.
No research has shown that clashing years between parents and child affect the child's health or character. Folk belief speaks of "a child overcoming the parents" when the axes are unfavourable; that is the wording of a belief, and no one has proven it.
Should one choose the year of a child's birth only for compatibility?
The folk way of matching ages is not enough of a basis for choosing a child's birth year. The birth year is only one of the four pillars, year, month, day and hour, that Bát Tự considers, and the three axes often point different ways, as the table above shows. Even within fate-studies books, Tử Vi đẩu số tân biên by Vân Đằng Thái Thứ Lang opens its general discussion of small children's charts with the sentence "reading the chart of a small child is a very difficult matter and cannot be decided at once". Having a child depends on health, family circumstances and work; the actual date and time of birth is decided by the health of mother and child, following the doctor's advice.
How are the baby's birth month and birth hour considered?
Bát Tự changes the month pillar at the twelve tiết (Lập Xuân, Kinh Trập, Thanh Minh, Lập Hạ, Mang Chủng, Tiểu Thử, Lập Thu, Bạch Lộ, Hàn Lộ, Lập Đông, Đại Tuyết, Tiểu Hàn), not at the first day of the lunar month, so the same birth date can fall in one lunar month yet carry a different month branch in Bát Tự.
The folk way of matching ages also compares the branch of the birth month and birth hour with the year branch of the child and of each parent, using the same tam hợp, lục hợp, tứ hành xung and lục hại tables as above; the schools do not agree on which axis weighs more.
Is the Kỷ Dậu year always good or always bad for having a child?
No. The stem Kỷ, which is Thổ, generates the branch Dậu, which is Kim; in reading the stem and branch within one year, the stem generating the branch is usually seen as smoother than the branch overcoming the stem, but that is only one trait of the year. The folk way of matching ages does not rank years as absolutely good or bad either: it only compares the child's birth year with each parent's birth year, so in the same year 2029 some parents count as favourable on one axis and unfavourable on another.
Nor is there any basis for the idea that having a child in a compatible year makes everything go smoothly. The relationship between parents and child depends on how they raise the child, the time they spend together and their living conditions, not on the can chi of the birth year.
A note from Nhật Nguyệt
Nhật Nguyệt's suggestion: if the expected birth date falls between 3 and 12 February 2029, or between 2 and 4 February 2030, check both the lunar year and the Bát Tự year pillar for the exact date and hour, because the Tết and Lập Xuân boundaries described above can give the two methods different year stems and branches. The compatibility reading is for reference only and does not replace the family's practical preparation.
