Conditional field required

Hi I can not make conditional fields mandatory. I leave my code

<fieldset>

<p>
<label for="book-date">Data di Arrivo</label>[date book-date id:book-date date-format:dd-mm-yy first-day:1 watermark "gg-mm-aaaa"]</p>
<p>
<label for="book-date">Data di Partenza</label>[date book-nights id:book-date date-format:dd-mm-yy first-day:1 watermark "gg-mm-aaaa"]</p>

<p>
<label for="book-adults">Adulti</label>[select* book-adults id:book-adults  default "1" "2" "3" "4" "5" ]</p>

<p class="float">
<label for="book-children-0-2">Bambini (0-11)</label>[select bambini  "" "1" "2" "3" "4"] </p>

[group group-529]
[group eta1]
<p class="float paddingLeft10">
<label for="book-children-0-2">Età 1</label>[select* eta-1 first_as_label "-" "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11"]</p>
[/group]

[group eta2]
<p class="float paddingLeft10">
<label for="book-children-0-2">Età 1</label>[select* eta-1 include_blank "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11"]</p>
<p class="float paddingLeft10">
<label for="book-children-3-11">Età 2</label>[select* eta-2 include_blank "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11"]</p>
[/group]

[group eta3]
<p class="float paddingLeft10">
<label for="book-children-0-2">Età 1</label>[select* eta-1 include_blank "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11"]</p>
<p class="float paddingLeft10">
<label for="book-children-3-11">Età 2</label>[select* eta-2 include_blank "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11"]</p>
<p class="float paddingLeft10">
<label for="book-children-3-11">Età 3</label>[select* eta-3 include_blank "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11"]</p>
[/group]

[group eta4]
<p class="float paddingLeft10">
<label for="book-children-0-2">Età 1</label>[select* eta-1 include_blank "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11"]</p>
<p class="float paddingLeft10">
<label for="book-children-3-11">Età 2</label>[select* eta-2 include_blank "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11"]</p>
<p class="float paddingLeft10">
<label for="book-children-3-11">Età 3</label>[select* eta-3 include_blank "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11"]</p>
<p class="float paddingLeft10">
<label for="book-children-3-11">Età 4</label>[select* eta-4 include_blank "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11"]</p>
[/group]

[/group]
<p style="clear:both">
<label for="book-rooms">Tipologia Camera</label>[select* book-rooms id:book-rooms first_as_label "-" "Camera Classic Standard" "Camera Vista Mare" "Camera Superior"]</p>
<p style="clear:both">
<label for="book-rooms">Trattamento</label>[select* book-service id:book-rooms first_as_label "-" "Camera e colazione" "Mezza pensione" "Pensione completa"]</p>
</fieldset>

<fieldset>
<p>
<label for="your-name">Il tuo Nome</label>[text* your-name id:your-name] </p>

<p>
<label for="your-phone">Il tuo Telefono</label>[text* your-phone id:your-phone] </p>

<p>
<label for="your-email">La tua E-mail</label>[email* your-email id:your-email] </p>

<p>
<label for="your-message">Qual è la tua Richiesta?</label>[textarea* your-message id:your-message] </p>

<label class="cgt-cf-privacy">[acceptance privacy] <br/>Si, acconsento al trattamento dei miei dati personali ai sensi della legge 196/2003 Italiana</a></label>

<p>[submit class:submit "Invia la tua Richiesta"]</p>
</fieldset>

The page I need help with: [log in to see the link]