Green’s Dictionary of Slang

1. (Aus.) a child [kid n.¹ (1)].

1905		Duke Tritton’s Letter n.p.: I hopped in. We drove about ten miles to his place and he introduced me to his Cheese and Kisses and four Tin Lids, two Mother’s Joys and two Twist and Twirls.
1912		Sport (Adelaide) 31 Aug. 14/1: They Say [...] That Bronco C. is beginning to leave the Kent Town ‘Tin Lids’ alone.
1952		Sun. Times (Perth) 20 Apr. 23s/3: His cheese-and-kisses shot through with his best China-plate. She took the tin lids with her.
1954		(con. 1940s) T.A.G. Hungerford Sowers of the Wind 254: You got any tin-lids that you know of?
1968		S. Gore Holy Smoke 12: He’s been a bash artist ever since he was a tin lid.
1982		N. Keesing Lily on the Dustbin 78: A ‘tin lid’ (kid) [...] is old enough for exposure to full blasts of family sarcasm.
1996		(con. 1964-65) B. Thorpe Sex and Thugs and Rock ’n’ Roll 7: [T]elling the cheese ’n’ kisses and tin lids that he was leaving them for true love with a big pair of tits.
1999		G. Seal Lingo 100: billy lids, sometimes tin lids, is rhyming slang for kids.
2002		Pete’s Aussie Sl. Home Page 🌐 tin lid: a kid.

2. a Jew [Yid n.¹ ].

1943		M. Harrison Reported Safe Arrival 10: Harry was a Jew. In his own phrase: a ‘tin-lid.’ Otherwise, a ‘four-by-two,’ a ‘Kangaroo,’ or a ‘five-to-two.’.
1960		J. Franklyn Dict. of Rhy. Sl.
1972		Dodson & Saczek Dict. of Cockney Rhy. Sl.