The full sentence is
小松鼠每天都到地里去，看看结花生了没有。
What is the function of 都 in this sentence? Is it to emphasize that the squirrel looked every day, or that it looked everywhere, or is it something else completely?
3 Answers
Chinese grammar wiki has a page for the "每 + measure word + noun + 都" structure to express "every".
Sometimes when the noun is also a measure word (like your example, 每天都), the "measure word" part does not show up in the structure.
And it is to emphasize the "every".
每 bla bla 都 is a very commonly seen structure in Chinese. You could leave 都 out.
小松鼠每天都到地里去，看看结花生了没有。
The little squirrel goes down to the ground every day, to see if the peanut plants have any fruit.
If the little squirrel 到地底去看看， he might have more luck! Maybe he could ask his friend 鼹鼠去看一看？
结: 结出果实 bear fruit
However, the peanut is generally known as a legume （豆科植物) and may or may not be fruit or a vegetable, depending on who you ask. Moreover, peanuts grow underground, not as fruit hanging on a plant :):)!
这只小松鼠点笨哦！！
小松鼠每天都到地里去
都 here is an adverb denoting the sense of all. It usually governs the word (每天 here) preceding it. E. g. 大家都去；我们都喜欢你；
