Simplify the following text for a Grade 5 native English-speaking person.
Original: In 1845 , as growth continued , MÃ 1\/4 ller decided that a separate building designed to house 300 children was necessary , and in 1849 , at Ashley Down , Bristol , that home opened .
Simplified: In 1845 , as they got bigger , MÃ 1\/4 ller decided that they would build another building for around 300 children . In 1849 , that home opened .