@absopugginglutely
I see your update - from 8.26 today, and I do hope that's true. He seemed to agree with you very quickly.
Have to say, I wonder the same as a few other posters on here.
Why on earth do people have separate finances when you're married with a kid?! Why are YOU paying for your JOINT CHILD out of YOUR MONEY?
So many women come on here with this same dilemma... 'I earn less than DH and am struggling to pay half of everything,' or 'my DH owes me money for paying for our shopping the other day, and hasn't given it to me yet,' and 'what our kids have come out of my money, and I am a tenner short for school uniform and DH won't give me a tenner to help.'
So. Bizarre. 
Seriously, FGS, tell him you want to pool your finances, because this is SO wrong. Hell would freeze over before I would be in a situation where I have to ask DH for money. shudder
Never done it in 25+ years together, and never would. Women are so vulnerable when they are in this situation. I actually really do feel sorry for them.
Me and DH earn roughly the same now, but in the past he has earned more (when our kids were younger and I worked less hours,) but he NEVER said 'I earn more so I get to keep more.' We always pooled finances.
I know half a dozen couples right now, who have been together around 15 to 20 years, and they STILL don't pool finances. (Some are married, some are not, and around 4 out of the six couples have kids...)
In each couple, it is the man who earns more, and she struggles to provide half towards everything, and lives in clothes that she's had for 10 years, while he squanders 100s of £ a month on his hobbies, new clothes every month, weekends away with his mates, and lots of frivolous shit.
In one couple we know, (and used to go to the pub with once a month or so,) he used to wave 20 pound notes about at the bar, and buy himself whiskies and brandies, while she tipped her purse upside down to try and find a few extra coppers for a coke.
I have even seen her asking for tap water as they have no money. Me and DH have bought drinks before for her (and other female friends who were skint,) because their DH/DP kept his money to himself,, and shared fuck-all.
We even saw one couple out one night, (who have always had separate finances, but he earns more) and when SHE went to the loo, he took £10 from her purse, and put it in his wallet.
We were so disgusted that we didn't socialise with this couple again. Shame for her, but we could not bear to see HIM again.
And joint accounts will not necessarily be 'cleaned out' if one partner leaves. You can easily make it so that no more than £200 can be withdrawn or spent without both signatures. (Or both people attending the bank to withdraw the money.)