The ornamental design for a toiletseat for children, as shown and described.
FIG. 1 is a front, right and top perspective view of a toilet seat for children, showing my design.
FIG. 2 is a rear, left and bottom perspective view thereof.
FIG. 3 is a front elevation view thereof.
FIG. 4 is a rear elevation view thereof.
FIG. 5 is a left side elevation view thereof.
FIG. 6 is a right side elevation view thereof.
FIG. 7 is a top plan view thereof.
FIG. 8 is a bottom plan view thereof.
FIG. 9 is an enlarged view of detail 9 in FIG. 1; and,
FIG. 10 is an enlarged view of detail 10 in FIG. 2.
The broken lines depict portions of the toilet seat for children that form no part of the claimed design. The dot-dash broken lines in FIGS. 1-2 and 9-10 depict the boundaries of the enlargements that form no part of the claimed design.