To reconnect with an estranged child in Bitlife, you will visit the child's profile tab under relationships and click the option that says reconnect. However, be warned, it may take a few tries before this option will work in the game - it may also depend on how much they dislike you.
That said, you will need to first have a child that you abandoned before you can even use this option. To have an abandoned child, you will need to find and click the abandoned option under their profile and click it.
After this, you will be able to use the reconnect option we mentioned to reconnect with them after around two years have passed in the game. You can make this time go by faster by aging up in the game. Once two years have passed, you will be able to use the reconnect option with your children.
However, as we stated already, it might not work the first time, so you will have to increase their relationship by sending them gifts slowly. Eventually, you will be able to reconnect with your children, and if you are trying to complete this week's challenge, you will finish one of the objectives.
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