The son of Motherwell manager Stephen Robinson has joined his father at Fir Park on a short-term contract.
Northern Ireland Under-21 international Harry Robinson has signed until the end of the season after leaving Oldham in January.
The 19-year-old made one substitute appearance for Oldham and spent the first half of the season on loan with Crusaders in his homeland.
Motherwell say the wide player will spend the rest of the campaign with the reserve squad. He has already played several matches for Maurice Ross's side as a trialist and netted in a 5-3 win over Morton after signing his deal.
David Turnbull played 60 minutes at Cappielow as he continues his comeback from knee surgery, although the midfielder saw a first-half penalty saved.