HELP!

I desperately need some help with this question:

A mare and a stallion have two offspring together. Four sites within a gene encoding muscularity show the following genotype in these animals:

Mare: AT CA TT GG
Stallion: AA AC CT CC
Offspring 1: AA CC CT GC
OffSpring 2: AT AA TT GC

a) Write down the four possible haplotypes each parent could have, assuming there was no recombination between the sites during transmission from parent to offspring.
b) Infer the haplotypes that two offspring have.

Many thanks in advance