We know that Tracy miscarries and then takes an opportunity to blame Becky because she thinks Steve and Becky are finding their way back together.
Tracy blackmails her mother into keeping her secret while she finds herself dug in deep to the point where she can't back out anyway, because the lie would drive Steve away.
Kate says that Tracy put the blame on Becky after fainting at Becky's flat and falling down the stairs. It was an impulse to blame Becky with opportunity knocking. Tracy was genuinly upset at losing the babies but as Kate says, "what she does would stop anyone from feeling sorry for her". Indeed! Kate defends Tracy's bitchy personality by saying that Tracy "is true to herself and doesn't let herself get walked all over. It's just not necessarily a good thing taken to the degree that Tracy takes it!"
Kate confirms that she's going to be around Coronation Street for some time to come.
Part one of the interview on Digital Spy is here and there's a bit more here.
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