Hi there, as one fellow-sufferer to another - errm, I think I may have Tinkerbell's older sister lol!
Mine's a ginger called Molly and her owners were at their wits' end with her aggression. They too had children including a baby. Now I don't know if the older kids had roughnecked with Moll; children can be thoughtless, but she's a little horror. As a small kitten, joining that household, she was responsible for the older cats moving out within a week.
When she came to me as an adolescent, I had three older cats - just that bit too old to play with her and give her a walloping if she got rough. Nothing better for teaching a cat to inhibit its clawing and biting than play-fighting with another cat. She and the boy got on best (sadly he's now passed on) and Emily, the eldest girl, will sock her one if Moll tries to bully her, but Mouse, the middle girl, is still nervous of her.
Luckily my back garden's secure; I soon realised that Molly roaming was not an option; small children lived nearby and if she encountered a child, or another cat, or dog, it was obvious she might do a lot of damage. She doesn't back down. For instance, if I put out a hand and tell her 'no' for clawing the duvet, say, her eyes narrow, and she gets a paw up and she'll sock ME. Like your Tinkerbell she goes for feet and legs; often if I was on the phone she would go into a corner and wee, I'm certain for attention, and like your Tinkerbell she sleeps on the bed with me; she follows me everywhere.
Recently she's shown signs of improvement; she's learning to sheath her claws if I absentmindedly waggle my fingers or 'stroke the wrong ear' as I call it. For a long while I couldn't stroke her at all.
This is after 4 years, five next February...
They're all different and I'm not claiming that what's worked for me will work for you, but during this time I've refused to play rough with her or even take any notice of her when she was aggressive; and making a mess or bullying the older ones earned her a telling-off. I don't shout, but I'll hiss or whisper fiercely at her - and she knows! Lots of praise for being a good girl - but I'm sure you're doing all this already.
There have been times in the last few years when I've been at screaming point with her! I realise how much patience you will have had to exercise with Tinkerbell.
There aren't any easy answers with a cat like this and perhaps I've just been lucky with Molly, or time has done it for us. She's still a pain, but she is so lovable - like you, when she's curled up on the bed with me, smiling and purring, I can forgive her anything. (Even making a mess in the bath - which she still does!) I DID try Feliway but she was immune - but other people have had good results with it.
So...I'm afraid I can't really suggest any advice but I know what you're going through and wish you well, I really do. Hopefully time will work its magic with Tinkerbell, but in the meantime, I sympathise, and all the very best (and sorry for the essay lol.)
