Simplify the following text for a Grade 7 native English-speaking person.
Original: Ireland thus became an integral part of the United Kingdom , sending around 100 MPs to the House of Commons at Westminster and 28 representative peers to the House of Lords , elected from among their number by the Irish peers themselves , except that Roman Catholic peers were not permitted to take their seats in the Lords .
Simplified: Ireland sent around 100 MPs to the House of Commons at Westminster and 28 peers to the House of Lords .