Phasing haplotypes from the crosses

Question

[ayeraselvan]

Hi all, I have sequenced data for two crosses of fruit flies, labeled RR1 (between Parent A and Parent B) and RR2 (between Parent B and Parent C). I possess phased variant information from the RR crosses but only have unphased data for Parents A and C. How can I infer the haplotype information of Parent B using the phased variant data from RR1 and RR2 in combination with the unphased data from Parents A and C?