This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
寴 combines 宀 (roof) with 親 (parent, intimate). The exact historical development is uncertain, but it likely expressed a concept of closeness or intimacy within a household.
Under a roof 宀, a parent 親 is close and intimate. This suggests a meaning of closeness or familiarity, but the kanji is rare and its meaning is not firmly established.
For シン, imagine a parent 親 under the roof 宀 sharing a heartfelt scene: the scene of closeness cues シン.