Parents have 2 and 3 blood groups which groups should be expected in the offspring.

Blood groups are inherited in the ABO system. The blood groups of children whose parents have blood groups 2 and 3 depend on the genotypes of their parents. If a:
a) parents are homozygous, i.e. AA and BB, then children can only have AB (4);
b) parents are heterozygous, i.e. AO and VO, then children can have any of the blood groups – OO (1), AO (2), VO (3) and AB (4);
c) if one has the AO genotype, and the other BB, then children may have BO (3) or AB (4);
c) if one has the AA genotype, and the other has VO, then children may have AB (4) or AO (2).