Family Maintenance never paid can I claim off inheritance

[Guest]

I divorced in 2014 , had two children 16 and 12. Ex husband left me with £50000 debt which I am still paying and he has never given me any. On top of that I was awarded court costs and his half of the house ( which he still hasn't signed over). He has never paid the court costs or paid Family maintenance either . He sold his sons and daughters Dudai gold , which was from their Grandfather and never gave them the money. I have recently discovered that his mother died in 2018 in which he /will received around £300,000.
My question is would I be able to make a claim against him so that my children can receive something and if so how ?
Thanks
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