Matt and His Family in The Sign of the Beaver
The Sign of the Beaver is a work of historical fiction set in colonial America, following a young boy left to guard his family's wilderness cabin while his father returns to fetch the rest of the family.
The provided context does not mention Matt or his family, nor does it explain why Matt might have been worried about them. Because that information is absent from the source material, the specific reason for his concern cannot be identified here.
Readers seeking insight into Matt's emotions and family situation are encouraged to refer to the original novel or a trusted literary summary.