The spouse is not an heir based on kinship by blood. However, the difference between the spouse’s heirship and foster child’s heirship is the groups they formed (also called classes) with other heirs in dissimilar proximities and the different hereditary shares they obtain.
Principle of the class constitutes the base level of law on succession. Briefly, only descendants form 1. class, lineal ancestors form 2. class, and kinship in the collateral line and cousins form 3. class. However, descendants are fundamental heirs and in case there is no descendant, the heir is transferred to the 2. class.
The spouse who is alive, can be an heir in every class. He/she can even be the only heir.
1. When the spouse becomes an heir together with the children of the legator, his/her share is one quarter of the whole heritage.
2. When the spouse becomes an heir together with the parents of the legator, his/her share is one half of the whole heritage.
3. When the spouse becomes an heir together with the collateral line and cousins of the legator, his/her share becomes three fourths of the whole heritage. However, there is a rule exists in this distribution. That is to say, if the spouse is the heir, only aunts and uncles of the legator can be the other heirs. Heirship of their descendants who are cousins of the legator ends up if the spouse is still alive.
The heirship of the spouse comes to an end with death or finalization of divorce. When divorce case continues, if one of the spouses dies and if heirs of that spouse continue to the process of the suit and prove that the other party who is alive has misbehaved, the heirship of the surviving spouse comes to a halt.
If there is a case that the marriage is invalid (superstitious) and if one of the spouses dies in the divorce process, and if the heirs of that spouse proved that the other party isn’t in good faith and the marriage is invalid, the heirship of the surviving spouse comes to an end.