Revised Standard Version takes this verse to be a continuation of the sentence started in verse 1, but it will be better in most languages to put a period at the end of verse 3 and begin a new sentence here.

Six were born to him in Hebron, where he reigned for seven years and six months: Good News Translation uses a more natural English way of referring to seven years and six months by saying “seven and a half years” (also Die Bibel im heutigen Deutsch, Nova Tradução na Linguagem de Hoje). Other languages should use the form that is most natural for them.

And he reigned thirty-three years in Jerusalem: According to 1 Chr 29.27; 2 Sam 5.4-5; and 1 Kgs 2.11, David ruled first in Hebron and after that in Jerusalem. Good News Translation, Revised English Bible, and some other modern versions highlight the fact that the reference to Jerusalem is a separate matter by beginning a new paragraph here. This is probably advisable in most other languages. It is also better to translate the common Hebrew conjunction at the beginning of this sentence as “Then” (New American Bible), “Later” (Bible en français courant) or “After that” (La Bible du Semeur) rather than literally as And. If it will not be clear in the receptor language that there was no overlap in the time that David ruled in Hebron and Jerusalem, New Living Translation provides a helpful model for this sentence with “Then David moved the capital to Jerusalem where he reigned another thirty-three years.”

Contemporary English Version combines verses 1-4 and restructures them helpfully as follows:

• King David ruled from Hebron for seven years and six months, and during that time he had six sons, who were born in the following order: Amnon, Daniel, Absalom, Adonijah, Shephatiah, and Ithream. Ahinoam from Jezreel was the mother of Amnon; Abigail from Carmel was the mother of Daniel; Maacah daughter of King Talmai of Geshur was the mother of Absalom; Haggith was the mother of Adonijah; Abital was the mother of Shephatiah; and Eglah was the mother of Ithream.
David then ruled from Jerusalem for thirty-three years.

Quoted with permission from Omanson, Roger L. and Ellington, John E. A Handbook on 1-2 Chronicles, Volume 1. (UBS Helps for Translators). Miami: UBS, 2014. For this and other handbooks for translators see here .