Complex sentence: He had three wives (including his consort Kusahahatahi) and his successor, Prince Shiraka (Emperor Seinei), was his son by his wife Katsuragi no Karahime.
Split into simpler sentences: He had three wives (including his consort Kusahahatahi). His successor, Prince Shiraka (Emperor Seinei), was his son by his wife Katsuragi no Karahime.