1.
They’d is a spoken form of ‘they had’, especially when ‘had’ is an auxiliary verb.
They’d both lived in this road all their lives.
2.
They’d is a spoken form of ‘they would’.
He agreed that ~ visit her after they stopped at Jan’s for coffee.
THEY’D
Meaning of THEY’D in English
Collins COBUILD. Толковый словарь английского языка для изучающих язык Коллинз COBUILD (международная база данных языков Бирмингемского университета) . 2012