See Knuckles, when a woman loves a pulsar very much...

"Yes," she said, as the Luma bounded away from Knuckles and into Rosalina's arms. "These Lumas are my children." She didn't feel the need to elaborate on it any more than that.

"It's no trouble at all, Knuckles," she greeted him with a smile. "It's a pleasure to meet you. Though I wish the circumstances were more ideal."