Complex sentence: Recognizing that Monaghan was an exceptionally outgoing child, his mother sent his picture to modeling agencies when he was three, he appeared on the cover of his first catalogue at the age of five, and appeared in his first regional commercial at the age of seven.
Split into simpler sentences: Recognizing that Monaghan was an exceptionally outgoing child, his mother sent his picture to modeling agencies when he was three. He appeared on the cover of his first catalogue at the age of five and appeared in his first regional commercial at the age of seven.