they have a lots of beefs and bad tension in the air between them in the beginning of season 4
also that season it's when tony tell chris that he will be his underboss in the future
i've always wonder what's really happen
it seems like patsy and sil have really formed a sort friendship between them
which made sil angry when chrissy been choose to be the acting capo
and tony realize that
and he took chrissy closer to him, until his drug problem became worse