Simplify the following text for a Grade 2 native English-speaking person.
Original: Sif does not respond , and the exchange turns to Beyla . Sif is additionally mentioned in two kennings found in poems collected in the Poetic Edda ; HymiskviÃ a ( where Thor is referred to as the `` Husband of Sif '' thrice ) , and Ã rymskviÃ a ( where Thor is once referred to as `` Husband of Sif '' ) .
Simplified: Thrud is the only daughter of Thor and Sif .