田衍 / Tian Yan
田衍 / Tian Yan appears in 《资治通鉴·周纪》08丨一代名将吴起惨死（3） as the son of 田和 and the successor whom the episode says should sit between Tian He and 田氏齐桓公 / 田武 in the Tian-family Qi line. The source uses him to show that early 齐国 chronology and naming are unstable enough that a simple received succession notice can hide violent internal transition.
In the episode’s account, Tian Yan is killed by his younger brother Tian Wu in 375 BCE. That murder opens the puppet phase in which Tian Wu installs Tian Yan’s son 公子喜 before later killing him and ruling directly.