You can claim your child if the following requirements are met. A resident alien is a person that has passed the substantial presence test (a calculation to determine if the person has been in the US for 183 days or more, see below). A legal resident is a green card holder.
https://ttlc.intuit.com/replies/5187060
You will be considered a United States resident
for tax purposes if you meet the substantial presence test for the calendar
year. To meet this test, you must be physically present in the United States
(U.S.) on at least:
- 31 days during the current year, and
- 183 days during the
3-year period that includes the current year and the 2 years immediately
before that, counting:
- All the days you
were present in the current year, and
- 1/3 of the days you
were present in the first year before the current year, and
- 1/6 of the days you
were present in the second year before the current year.