national savings childrens bonds

[wulluff]

I have 2 lots of these for my kids (12&16) and want to cash them in. However they are in joint names of me and my ex wife. It seems straightforward enough to have the bonds repaid but I either have to get my ex's permission or - give an explanation of why the "responsible person" has changed.

I don't think "she's a frigid bint of a control freak" would work, but I can't find any info on what the criteria is - ie could I nominate the new Mrs W???

TIA