The 1901 census is easy to use, if u are searching on line you need to have the name and location of the person you are looking for as a basis for confirming it is the correct entry. If it is a common surname, without a location you would be spending ages looking. How old would they be in 1901? The census took place in early April and so if they were only born after then, they would not be included, but their parents would be. The more information you have about siblings, the easier it will be to identify the correct family group.