Ricky Sbragia is happy for the pair after their senior international call-ups.
The two sides meet in a huge Tyne-Wear derby this weekend.
Rangers signed Billy King on loan from Heart of Midlothian in the January transfer window.
Rangers winger Barrie McKay has been playing well this season.
How does Dick Advocaat compare to the last five full-time Sunderland managers?
Jack Harper is reportedly being approached by the Spain squad, having not been selected by Scotland.
Scotland Under-19's manager justifies leaving Real Madrid's Jack Harper out of his squad.