Who is on the hook for each property ?
What kind of income security (job security) do you have ?
I know a few couples in a similar situation ,
1 ) Stop paying mortgages on investment properties now.
2) Stop paying mortgage on home now ,its not worth fighting for if its so run down.Stop paying credit cards , overdrafts etc
3) Build up a war chest with the rent received from investment properties
4) Move you're Family into a rental house , in the same area or close by to lesson disruption to the kids , max rent 1500
5) Ignore the banks letters/phone calls until you get court papers for repossessions , then consent to the repossessions.
6) Consent to judgments sought by bank against you on the properties when you receive the papers .
7) Turn up in court when you are required to have your means examined by a judge to see how much your Family finances can afford to pay towards the outstanding judgments / if there are 3 judgments against you (one for each repossessed property )
I don't think any of the banks would try bankrupt you,too costly to them and no chance of getting anything from you.
I think UK bankruptcy is a last resort for you unless everything is in your sole name. (mortgages)
Down the line
You and your family will be much happier in your lives.
You will be renting a house you are happy to live in with your family if not you can move .
You may still have a decent income.
If you loose your job/s you will qualify for rent allowance having rented the house for at least 6 months.
A judge may eventually order you to pay circa 100 -150 off each judgment going forward (or less) after accessing your means. He first takes into consideration your families financial needs, but i'm sure you could live with that.
Judgments are unenforceable after 12 years.
If you anticipate any inheritance in the future from parents etc. ask them to be willed to your kids instead.
Forget about getting a loan or credit for a long time.
Put the nightmare behind you and forget about trying to keep hold of these properties.Your family will thank you for it , Ive seen it happen.
If the above is against your religion or morals then disregard