Midrasz do Diwrej ha-jamim I 4:5

(Ex. 1, 21) And it came to pass because the midwives feared God that He made them houses. Rab and Levi both explain the above passage: One says that this means kingly houses and the other said it means priestly and Levite houses. The latter interpretation refers to Moses, and the former contends that kings came forth from Miriam who was also one of the midwives, for it is written (I Chr. 1, 2) And Azubah died when Kaleb took unto himself Ephroth who bore unto him Chur and again it is written (I Sam. 17, 22) Now David was the son of that Ephritite, [hence David was of the same family as Miriam]. (I Chr. 2, 18) And Kaleb the son of Chetzron begot children of Azubah, and of Jerioth and these were her sonss Jeshner, Shobah and Ardon. Is he then the son of Chetzron? Behold he is the son of Yephunah, as stated (Num. 13, 6) He was called with the last name because he turned away from the advice of the spies. And again is he not the son of Kenaz, as it is written (Hosh. 15, 17) And Othniel, the son of Kenaz, the brother of Kaleb, captured it? Said Raba: "He was a step-son to Kenaz." (Fol. 12) This can be proved by the following — he is called a Kenizzite, but not the son of Kenaz. Hence the inference is maintained. (Ib. 14, 14) Azubah, refers to Miriam, "why was she called Azubah? Because every young man forsook her in the beginning; she begot, behold, she was married to him and she begot him? Said R. Jochanan: "Whoever marries a man from a respectable family for heavenly sake is considered by Scripture as if he begot her." Yerioth she was called, because her face was greenish like the curtains of the Temple. And these were her sons. Do not read Baneha (her sons) but boneha {who built her up); yashar means who kept himself straight in the right path, [did not listen to the spies]; Sho'ab means, who turned himself away [from his evil inclinations]; Ardon means who rebelled against his evil inclination, and according to others because his face was as prim as a rose. (I Chr. 4, 5) And Aschuhr the father of Teke'ah had two wives, Chelba and Nea'arah; i.e., Ashchur refers to Kaleb, and why was he called Ashchur; because he darkened his face because of the many fasts he observed, Abi, who became like a father to his wife; teko'ah, who attached his heart unto his Father in heaven; there were two wives, the one Miriam became like two wives; Chela and Na'arah, neither was her name Chela nor Na'arah, but it means in the beginning she was sick, and at the end she became young, (Ib., ib. 7) And the sons of Chilah were Zareth, Zochar and Ethnan; i.e., Zureth means that she caused grief and animosity to her friend [because of her beautiful] appearance; Zochar means that her face was like the mid-day; Ethnan because she appeared very handsome.

(I Chronicles 4:5) "And Ashchur, the father of Tekoa, had two wives, Chelah and Na'arah." Ashchur is Calev. Why was he called "Ashchur"? Because his face was "blackened" (hushcharu") with fasting. "the father" — He was like a father to her (Miriam). "Tekoa" — He "pegged" (taka) his heart to his father in heaven. "two wives" — Miriam, who became to him like "two wives." "Chelah and Na'arah": At first she was sick (cholah), and then she "awakened" (na'arah). (Ibid. 7) "And the sons of Chelah were Tzereth, Tzochar, and Ethnan": Tzereth — she became a "vexation" (tzarah) to her co-wife, (who envied her). Tzochar — Her face was resplendent as mid-day (tzoharayim). "and Ethnan" — Anyone who saw her brought an "exchange" (for cohabitation) to his wife. (Ibid. 8) "And Kotz begot Anuv and Hatzovevah": "Kotz" is Calev, who "spurned" (katzath) the counsel of the spies. "Anuv" — he generated good in the bringing of the grape cluster (viz. Bamidbar 13:23) for if not for Calev they would not have brought it. "and Hatzovevah" — he did the will (tzivyon) of the Holy One blessed be He. "and the families of Acharchel the son of Charum. "and the families of Acharchel" — This is Miriam, viz. (Shemot 15:20) "and all the women went out after ("achar") her (Miriam) with timbrels and dances." "and the families" — He (Calev) merited establishing families from her. "the son of Charum" — This is Yocheved, of whom (the Cohanim) it is written (Bamidbar 18:14) "Every devoted thing ("cherem") in Israel shall be yours," (the Cohanim - Levites descending from Yocheved). Variantly: This ("Charum") is Miriam from whom there issued forth David, whose kingdom was exalted ("romem") by the Holy One Blessed be He, viz. (I Samuel 2:10) "And He will give strength to His king and He will exalt the horn of His anointed one." We find, then, that David came from the descendants of Miriam — whence we derive "One who draws near (to Israel) is drawn near by Heaven."