I have been divorced for 8 years in the first 3 years I had my son Thursday thru Sunday and that worked out great. As time went on my son would ask to stay over a extra day and then all week which was fine eventually he was with me full time . When his mother who is remarried gave birth to another boy she totally forgot about my son and months would go by without him seeing his mother. I always thought it was temporary since she was a great mother while we were together so I never thought about asking for any support plus I loved having my son and didn't want things to change. She never offered me any kind of help even though I have had financial problems and she makes close to $100,000. She has took him clothes shopping , bought books for school and helped buy him a car
If there was no order legally obligating her to pay child support, you cannot collect back support (aka arrears) from her.
Car / Auto Accident Lawyer
The obligation to pay child support arises with a court order that is signed by a Judge. A child support order can only be retroactive (ability to go after past months) to the day the request for child support is actually filed with the court. If that request was never made, there is no retroactivity (or arrears).