Me!
Dd2 was born when dd1 was 16 months - so was younger. Dd1 had been at Nursery for 3 days a week since she was 10 months old.
I took the full year off with dd2 - dd1 still went to Nursery 3 days a week.
It was good for dd1 - she was/is very happy at Nursery - it is a good one.
I was able to have some days alone with dd2 - I also wanted to be more successful with bf dd2 than I was with dd1 - I was!
I also didn't feel guilty about unloading the dishwasher etc when dd1 was at home instead of sticking etc with her - as she was doing 'crafty' things at Nursery.
As it happens, I had to have an emergency c-section with dd2, so dd1 went to Nursery full-time for the first month. Dd1 could walk but often chose not to - I was not in a position (literally) to pick her up. Don't know what I would have done if dd1 wasn't going to Nursery.
I was/am lucky in that financially dd1 going to Nursery was fine.
IMHO experience if you can afford it then go for it - but make sure you spend a lot of quality time with dd1.
It worked very well for me, dd1 is now 31 months and dd2 is 15 months - they are both at Nursery and I am back at work - and we are all happy (although I am a bit stressed - but that is another story! )
HTH