Sunup and Wee hours

Sunup noun - The first appearance of light in the morning or the time of its appearance.

Wee hours and sunup are semantically related in dawn topic. In some cases you can use "Wee hours" instead a noun "Sunup".

Sunup and wee hours are semantically related in dawn topic. You can use "Sunup" instead a noun phrase "Wee hours", if it concerns topics such as beginning of day, first part of the day.