בָּנִ֛ים אֲשֶׁר־יִוָּלְד֥וּ לָהֶ֖ם דּ֣וֹר שְׁלִישִׁ֑י יָבֹ֥א לָהֶ֖ם בִּקְהַ֥ל יְהוָֽה׃ (ס)
The children of the third generation that are born unto them may enter into the assembly of the LORD.
Sifrei Devarim
(Devarim 23:9) "The banim which will be born to them, the third generation shall come for them into the congregation of the L-rd": "banim" (lit.,) "sons," and not daughters. These are the words of R. Shimon. And the sages say: "which will be born to them": to include the daughters.