tabe - at that time; māyera garbhe - the womb of the mother; haya - was; sei ta' kumāra - that son; śivānanda ghare gele - when Śivānanda Sena returned home; janma haila tāra - he was born.

The son was in the womb of Śivānanda’s wife, and when Śivānanda returned home the son was born.