yes by all means if you have a old stock cock and he is of good stock then put him on with a daughter to keap the lines then put the youngster off them to stcock to cross out best birds to use for a cross i have done it this year with stormqueens great great grandson as hes 15 now i got 1 off him but hes a cracker just so i can keap the stormqueen lines as my uncle did the same with the old cock i have he was double inbred to stormqueen so i have just done the same