Complex sentence: Owen was sent to Newgate prison making his way to Wales, his children Edmund and Jasper and possibly their unknown sister were given to Katherine de la Pole who was a nun at Barking Abbey in Essex.
Split into simpler sentences: Owen was sent to Newgate prison, making his way to Wales. Owen's children Edmund and Jasper, and possibly their unknown sister, were given to Katherine de la Pole who was a nun at Barking Abbey in Essex.