There are 3 ties in every level including both Shorts levels, Dad Romance and Medical Mess and a secret level hidden within the Aquatic Fun Center level, Toilets and Trouble, that's pretty easy to miss and contains 3 ties.
To find Toilets and Trouble - at the beginning of the Aquatic Fun Center level you will need to get a ticket to enter the fun center. After you get the ticket there will be a turnstile that your family is waiting for you in front of. Instead of going through the turnstile, go into the mens room on the right and flush yourself down the middle toilet. The 3 ties in this level are all lined up next to each other at the end out in the open.
The game also has tracker for the ties in the extras menu showing every level and which ties you have and haven't collected for each.
I KICKER I - "This achievement cannot be unlocked if your country and language are set to Canada/french in that version of the game the short level of the restaurant only count 2 ties out of 3 (the one under the table doesn't count). To fix this change your location and language to united states and english.im not sure if the other location are glitched too but if your achievement is stuck 97% you should try this method if your sure you found them all