In 2015 We paid Child Care Expenses but forgot to claim them when we filed in 2016, Can I claim this now?

No, you cannot claim child care expenses paid in 2015 on your 2016 tax return.

If you wish to claim them, you'll need to amend your 2015 tax return.

Please read this TurboTax FAQ on how to amend a tax return:

 https://ttlc.intuit.com/replies/3288565