When your baby is a little older, you can start adding pumping to your daily routine. While it's not necessary, it's comforting to have a little bit of a stash of milk built up before you return to work. Warning - be sure to read this page on smart use of your freezer stash!
You must file a tax return if your net earnings from self-employment were $400 or more. So consider this: you may be 36 years old, single and make less than $10,000 per year in regular employment income, but if you have a side business that nets you more than $400, you will need to file a federal tax return.
Well, it is true that everyone has to pay taxes, there are exceptions, especially for people age 65 and older. But there is no age at which you stop filing. You just need to check your income and the tax rules every year to determine if you need to report any of your income.