See also

Baudouin DE HAINAUT's parents: Baudouin II "de Jérusalem" DE HAINAUT (1056-1098) and Ida VAN LEUVEN-BRABANT (1061-1139)
Baudouin DE HAINAUT's siblings: Arnulf I DE HAINAUT (c. 1089-c. 1150), Ida DE HAINAUT (c. 1085-c. 1138), Oda VAN AERSCHOT ( - ) and Aelidis DE HAINAUT (c. 1085-c. 1155)
Yolande DE WASSEMBERG's parents: Gerard III DE WASSEMBERG (1058-1129) and Clémence DE POITOU VAN GLEIBERG (1057-1142)

Family of Baudouin III DE HAINAUT and Yolande DE WASSEMBERG

Husband:
Baudouin III DE HAINAUT (1088-1133)
Wife:
Yolande DE WASSEMBERG (1090-1131)
Children:
Richildis III VAN BERGEN EN HENEGOUWEN (c. 1105-c. 1179)
Baudouin IV DE HAINAUT (1108-1171)
Marriage:

Husband: Baudouin III DE HAINAUT

Baudouin III DE HAINAUT

Name:
Baudouin III DE HAINAUT
Sex:
Male
Father:
Baudouin II "de Jérusalem" DE HAINAUT (1056-1098)
Mother:
Ida VAN LEUVEN-BRABANT (1061-1139)
Birth:
1088
Death:
1133 (age 44-45)

Wife: Yolande DE WASSEMBERG

Yolande DE WASSEMBERG

Name:
Yolande DE WASSEMBERG
Sex:
Female
Father:
Gerard III DE WASSEMBERG (1058-1129)
Mother:
Clémence DE POITOU VAN GLEIBERG (1057-1142)
Birth:
1090
Geldern, North Rhine-Westphalia, Germany
Death:
1131 (age 40-41)
Hainault, Belgium

Child 1: Richildis III VAN BERGEN EN HENEGOUWEN

Name:
Richildis III VAN BERGEN EN HENEGOUWEN
Sex:
Female
Spouse:
Everhard II DE MORTAGNE VAN DOORNIK (1105-1159)
Birth:
c. 1105
Death:
c. 1179 (age 73-74)

Child 2: Baudouin IV DE HAINAUT

Son: Baudouin IV DE HAINAUT

Spouse: Alice DE NAMUR

Name:
Baudouin IV DE HAINAUT¹
Sex:
Male
Spouse:
Alice DE NAMUR (1110-1168)
Birth:
1108
Mons, 7000, Hainaut, Belgium
Death:
8 Nov 1171 (age 62-63)
Valenciennes, Nord-Pas-de-Calais, France
Burial:
St. Waldthud Abbey, Mons, Belgium

Sources

1.: http://gw.geneanet.org/wmeier.