Yes, I think it's going to be a busy day at LHR...

The other advantage of the kids in row 18 is that whoever is in 19D can see them quite easily (or at least you could with the traditional version of new club world).

Another solution if they're likely to beat 7 bells out of one another if sitting side by side for any length of time would be to put one of them (the shorter one) in 19D whilst you have an adult in 19E then an adult & child in 18 EF.

It's interesting - there has been no shortage of debate on the board about the pitfalls of the new deating policy and what if's for family travel, but this is the first time we've seen the flaw played out not to the perfect advantage of the passengers (but it could have been far worse than this - even 18 DE and 19 EF would have been worse!)