caring for someone question

Hello, we are on a couples Income related ESA, we also receive the severe disability premium [£165.80] as a couple [husband in support group & PIP and wife on standard care pip], my wife is also an appointee for my adult son [over 30 years old and in ESA support group and PIP], I have a few questions; -

1. As we are awarded SDP because we don’t claim carers allowance would SDP still be awarded if my wife cared for me [or son] for more than 35 hours even though she doesn’t get a carers allowance or would the SDP only stop if she claimed carers allowance?

2. If she did care for me [or son] for 35 hours or more would this exempt her from attending looking for work with a work coach or would the exemption only apply if she was actually claiming a carers allowance?

3. as my wife is an appointee for my son would this alone exempt her from attending looking for work with a work coach regardless of caring for more or less than 35 hours?

Thank you very much for any help or advice in working through the Migration process